p401 problem
My engine light keeps coming on with this same problem. on 1999 Toyota RAV4

The EGR value has been replaced. The engine code was clear out, but a couple of days later, my engine light came back on with the same code. What do I need to do to correct this problem so that my engine light will not come back on with this code? Do I need to replace my EGR value again or is there somethin else I need to look at to correct this problem? Please help!

Asked by for the 1999 Toyota RAV4
Apply vacuum to the top vacuum port to the egr valve while the engine is idling. The engine should die out almost instantly. If not, you need to clean the carbon out of the ports.If thats not the problem, check the wiring for shorts or opens.